Logical Reasoning - Number Series - Discussion
Discussion Forum : Number Series - Type 1 (Q.No. 16)
Directions to Solve
In each series, look for the degree and direction of change between the numbers. In other words, do the numbers increase or decrease, and by how much
16.
Look at this series: 80, 10, 70, 15, 60, ... What number should come next?
Answer: Option
Explanation:
This is an alternating addition and subtraction series. In the first pattern, 10 is subtracted from each number to arrive at the next. In the second, 5 is added to each number to arrive at the next.
Discussion:
83 comments Page 2 of 9.
Angel said:
1 decade ago
Here two series go at a time.
First 80, 70, 60, .. (subtract 10).
Second 10, 15, .. (add 5).
Now join them 80, 10, 70, 15, 60, 20, 50, 25, 40, 30, 30, 35, 20, .
So according to the question our answer should be 20.
First 80, 70, 60, .. (subtract 10).
Second 10, 15, .. (add 5).
Now join them 80, 10, 70, 15, 60, 20, 50, 25, 40, 30, 30, 35, 20, .
So according to the question our answer should be 20.
Ruqaiya said:
3 years ago
80, 10, 70, 15, 60,
You have to add differences.
80-10=70,
10-70=60,
70-15=55,
15-60=45.
Double differences.
70-60=10,
60-55=5,
55-45=10.
So next no is 5.
45 - 5 = 40.
40 - 60 = 20.
You have to add differences.
80-10=70,
10-70=60,
70-15=55,
15-60=45.
Double differences.
70-60=10,
60-55=5,
55-45=10.
So next no is 5.
45 - 5 = 40.
40 - 60 = 20.
(15)
Shweta said:
1 decade ago
80,10,70,15,60,
nw we hav to seperate this
80,70,60,50,
[this is decresed by 10]
10,15,20,
[this is increased by 5]
nw compare both which hav least num at the end.20 is the ans
nw we hav to seperate this
80,70,60,50,
[this is decresed by 10]
10,15,20,
[this is increased by 5]
nw compare both which hav least num at the end.20 is the ans
Gurmeet Soni said:
8 years ago
80,70,60 _"10"
10,15,20_ "5"
First Numbers " Subtraction"
80 - 10 = 70
70 - 10 = 60
Second Numbers " Addition"
10 + 5 = 15
15 + 5 = 20.
10,15,20_ "5"
First Numbers " Subtraction"
80 - 10 = 70
70 - 10 = 60
Second Numbers " Addition"
10 + 5 = 15
15 + 5 = 20.
(2)
Prince Bhanu said:
2 years ago
@Kitana.
80,10,70,15,60,-?
Here 10 will be subtracted,
80 - 10 = 70
70 - 10 = 60.
For the remaining, 5 will be adding 10 + 5 = 15.
So, 15+5 = 20!
So the answer is 20.
80,10,70,15,60,-?
Here 10 will be subtracted,
80 - 10 = 70
70 - 10 = 60.
For the remaining, 5 will be adding 10 + 5 = 15.
So, 15+5 = 20!
So the answer is 20.
(17)
Talha said:
2 years ago
80, 10, 70, 15, 60, 20.
Explanation;
Differences Between Them.
(-70+60-55+45-40).
Because the difference is (-10-5+10-5).
So; (45-5=40 Then 60-40=20).
Answer = 20.
Explanation;
Differences Between Them.
(-70+60-55+45-40).
Because the difference is (-10-5+10-5).
So; (45-5=40 Then 60-40=20).
Answer = 20.
(12)
Vinil said:
1 decade ago
Third number = first number-10, fifth number = third number-10.
Fourth number = second number + 5, fourth number + 5 = sixth number.
Therefore here 20 is answer.
Fourth number = second number + 5, fourth number + 5 = sixth number.
Therefore here 20 is answer.
Irisha singh said:
11 months ago
Let's see the sequence of 80, 70 and 60 there's reduced by 10 and in another sequence of 10, 15 there's an additional of 5.
So the answer is 20.
So the answer is 20.
(10)
Nandini said:
1 decade ago
80 70 60 is the 1st order series it decrease 10.
80-10 = 70.
70-10 = 60.
10 150 is second order series it increase 5.
10+5 = 15.
15+5 = 20.
80-10 = 70.
70-10 = 60.
10 150 is second order series it increase 5.
10+5 = 15.
15+5 = 20.
Mannu kumar said:
9 years ago
80-10=70
70-10=60
60-10=50 and so on...
NW
10+5=15
15+5=20
20+5=25 and so on.
Now your final series is 80, 10, 70, 15, 60, 20, 50, 25.
70-10=60
60-10=50 and so on...
NW
10+5=15
15+5=20
20+5=25 and so on.
Now your final series is 80, 10, 70, 15, 60, 20, 50, 25.
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